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L Rombauts

Publications and source records attributed to L Rombauts.

At least 19 recordsLinked to original sources
PubMed2006

GnRH antagonists in ovarian stimulation for IVF.

The present review describes, on the basis of the currently available evidence, the consensus reached by a group of experts on the use of gonadotropin-releasing hormone (GnRH) antagonists in ovarian stimulation for IVF. The single or multiple low-dose administration of GnRH antagonist during the late-follicular phase effectively prevents a premature rise in serum luteinizing hormone (LH) levels in most women. Although controversy remains, most comparative studies suggest a slight, not significant reduction in the probability of pregnancy after IVF using GnRH antagonist versus GnRH agonist co-treatment. Published meta-analyses suggest that this slight difference in pregnancy rates is not attributed to chance. Further studies applying varying treatment regimens and outcome measures are required. Data are not in favour of a need to modify the starting dose of gonadotropins. Data are not in favour of increasing gonadotropin dose at GnRH antagonist initiation. The addition of LH from the initiation of ovarian stimulation or from GnRH antagonist administration does not appear to be necessary. Replacement of human chorionic gonadotropin (HCG) by GnRH agonist for triggering final oocyte maturation is associated with a lower probability of pregnancy. The optimal timing for HCG administration needs to be explored further. GnRH antagonist initiation on day 6 of stimulation appears to be superior to flexible initiation by a follicle of 14-16 mm, although earlier GnRH antagonist administration is worth further evaluation. Luteal phase supplementation in GnRH antagonist protocols remains mandatory in IVF. Effects of GnRH antagonist co-treatment on the incidence of ovarian hyperstimulation syndrome remains uncertain, although a trend is present in favour of the GnRH antagonists. The role of GnRH antagonists in ovarian stimulation for IVF appears to be promising, although many questions regarding preferred dose regimens and effects on clinical outcomes remain.

Chorionic Gonadotropin↗
PubMed2003

Ultrasound prediction of risk of spontaneous miscarriage in live embryos from assisted conceptions.

OBJECTIVE: An accurate method to predict subsequent miscarriage in live embryos has not yet been established. This pilot study aimed to determine the most discriminatory ultrasound-based model for predicting spontaneous miscarriage after embryonic life was first detected in assisted conceptions. A method for estimating individual risk of miscarriage was developed. METHODS: This was a prospective cross-sectional survey of 322 live singleton embryos in women from an assisted reproductive technology program. Mean sac diameter (MSD), crown-rump length (CRL), embryonic heart rate (EHR), maternal age and gestational age at the first transvaginal scan detecting embryonic life (between 42 and 62 days) were observed. These variables were included in a multivariate model for predicting spontaneous miscarriage occurring prior to 20 weeks. MSD, CRL and MSD minus CRL were assessed in univariate logistic regression analyses. The global diagnostic accuracy of each model was compared directly using receiver-operating characteristics (ROC) curves. RESULTS: The multivariate model demonstrated the best ROC curve for predicting miscarriage (ROC area 0.87; 95% CI, 0.80-0.95). The separate univariate analyses had less diagnostic accuracy. In particular, MSD - CRL had a significantly smaller ROC area (0.65) than did the multivariate model (P < 0.01). CONCLUSIONS: The most discriminatory test for predicting spontaneous miscarriage in live embryos was a multivariate model, which allows estimation of individual risk levels.

Abortion, Spontaneous↗
PubMed1999

Diagnostic accuracy of transvaginal hydrolaparoscopy in infertility.

OBJECTIVE: To determine whether the accuracy of transvaginal hydrolaparoscopy is comparable to that of standard laparoscopy for the diagnosis of infertility. DESIGN: Prospective, comparative study. SETTING: General hospital in Belgium. PATIENT(S): Ten infertile patients without obvious pelvic pathology. INTERVENTION(S): Two gynecologists independently performed transvaginal hydrolaparoscopy and standard laparoscopy and reported the observations in a confidential manner to a third person. MAIN OUTCOME MEASURE(S): Endometriosis, adhesions, and other pelvic pathology related to infertility. RESULT(S): Minimal or mild endometriosis was diagnosed in seven patients and sequelae of pelvic inflammatory disease in one patient at both procedures. The interobserver agreement for tuboovarian adhesions was 95% at transvaginal hydrolaparoscopy and 74% at standard laparoscopy. Ovarian adhesions were detected in 63% at transvaginal hydrolaparoscopy and in 37% at standard laparoscopy. CONCLUSION(S): Transvaginal hydrolaparoscopy is comparable in accuracy to standard laparoscopy for the diagnosis of adhesions and endometriosis in infertile patients without obvious pathology.

Endometriosis↗
PubMed1999

Cumulative pregnancy and live birth rates in women with antiphospholipid antibodies undergoing assisted reproduction.

The aims of this study were to investigate the influence of antiphospholipid antibodies (APA) on cumulative pregnancy and live-birth rates in patients undergoing assisted reproductive treatment. Serum samples from 173 patients were collected prior to initiation treatment cycle and tested by enzyme-linked immunosorbent assay (ELISA) for the presence of immunoglobulin (Ig)G, IgM and IgA against cardiolipin, phosphoserine, phosphoethanolamine, phosphoinositol, phosphatidic acid, and phosphoglycerol. Fifty-six samples from patients who had at least two failed cycles by assisted reproductive treatment were also tested by a bioassay for the presence of lupus anticoagulants. Both cumulative pregnancy and live birth rates were not affected by the presence of any specific or any number of seropositive APA. There was no association between multiple assisted reproductive treatment failures and APA seropositivity. Neither the serum concentration of any of the 18 APA, nor the number of positive APA was correlated with the number of assisted reproductive treatment failed cycles or affected the probability of pregnancy. No patient was found to be positive for lupus anticoagulants. Using life table analyses, which has been recognized as the most appropriate method available to analyse assisted reproductive treatment results, we conclude that there is no relationship between circulating APA and assisted reproductive treatment outcome. APA do not affect the early process of implantation or maintenance of pregnancy among assisted reproductive treatment patients.

Abortion, Spontaneous↗
PubMed1998

Recruitment of follicles by recombinant human follicle-stimulating hormone commencing in the luteal phase of the ovarian cycle.

OBJECTIVE: To investigate, in patients who previously had a suboptimal ovarian stimulation cycle, the benefit of starting ovarian stimulation before the onset of menses. DESIGN: Prospective, randomized, controlled study. SETTING: A tertiary referral center for infertility treatment. PATIENT(S): Forty patients undergoing IVF or GIFT from whom only 3-6 oocytes were retrieved in their last cycle. INTERVENTION(S): Recombinant human FSH was administered before the onset of the menstrual period (experimental group) or in the early follicular phase after the onset of menses (control group). MAIN OUTCOME MEASURE(S): The number of oocytes retrieved. RESULT(S): Patients in the experimental group were ready for oocyte retrieval on menstrual cycle day 11 instead of cycle day 14. The number of oocytes retrieved was not significantly different between the two groups. CONCLUSION(S): Poor responders do not benefit from commencing recombinant human FSH therapy in the luteal phase.

Adult↗
PubMed1998

Transvaginal salpingoscopy: an office procedure for infertility investigation.

OBJECTIVE: To evaluate the feasibility of salpingoscopy as an office procedure using transvaginal access to the pelvic cavity. DESIGN: Descriptive study. SETTING: Gynecology office. PATIENT(S): Infertile women with no obvious pelvic pathology. INTERVENTION(S): Transvaginal Veress needle puncture and peritoneal distension by saline. MAIN OUTCOME MEASUREMENT(S): Visualization of distal tubal segment. cannulation, and salpingoscopy. RESULT(S): The fimbriae were visualized in all patients. Cannulation of the distal tubal segment was achieved without manipulation of the tube in 20% before ovulation and 55% in the early luteal phase. CONCLUSION(S): Transvaginal fimbrioscopy and salpingoscopy can be performed as an office procedure in patients without obvious pelvic pathology. In combination with hydrolaparoscopy and dye hydrotubation, the technique provides comprehensive screening of the tuboovarian structures in the early stage of infertility investigation.

Ambulatory Surgical Procedures↗
PubMed1998

Different influence of incongruent follicular development on in vitro fertilization-embryo transfer and gamete intrafallopian transfer pregnancy rates.

OBJECTIVE: To compare the influence of incongruent (asymmetric) follicular development on treatment outcome in IVF-ET and GIFT cycles. DESIGN: A retrospective comparative study. SETTING: Tertiary referral center for infertility. PATIENT(S): Five hundred forty-three consecutive assisted reproduction cycles (428 IVF-ET and 115 GIFT) in 422 infertile patients. INTERVENTION(S): Controlled ovarian hyperstimulation (COH) and IVF-ET or GIFT. MAIN OUTCOME MEASURE(S): The incongruity ratio as a parameter of the asymmetry in follicular development and pregnancy rate (PR). RESULT(S): For GIFT cycles, the PRs were 37.8% and 15.7% in cycles with congruent and incongruent follicular development, respectively. However, for IVF-ET cycles, the PR was not affected by incongruent follicular development: 28.2% and 29.0%, respectively. An inverse relationship was observed between the degree of incongruity and the estimated probability of pregnancy in GIFT cycles but not in IVF-ET cycles. Neither the side of the dominant ovary nor the degree of incongruity were consistent in consecutive cycles. CONCLUSION(S): Incongruent follicular development during COH has a significantly negative influence on the outcome of GIFT cycles but not on the outcome of IVF-ET cycles. The reason for this difference is not clear. We recommend considering IVF-ET instead of GIFT if incongruent follicular development occurs.

Adult↗
PubMed1998

Intracytoplasmic sperm injection in the treatment of male subfertility.

OBJECTIVE: To evaluate the results obtained after intracytoplasmic sperm injection (ICSI) in couples with male factor subfertility. DESIGN: Retrospective analysis of results obtained after ICSI in the unit of in vitro fertilisation in a private centre for infertility. RESULTS: Application of ICSI in treatment cycles for male subfertility resulted in a fertilisation rate of 62%. An embryo transfer was done in 98% of the cycles, resulting in a 24% pregnancy rate/ET or 22% per cycle. CONCLUSION: ICSI is the first microfertilisation technique with reproducible high fertilisation rates in different centres and the method of choice in the treatment of severely impaired sperm quality. Although, up to now, no higher incidence of congenital malformations has been reported, except for sex chromosomal anomalies, careful genetic counselling is mandatory because of the risk of transmitting genetically defined male subfertility to the next generation.

Adult↗
PubMed1998

Performance of the sperm quality analyser in predicting the outcome of assisted reproduction.

The present study was undertaken to assess the relationship between the results of conventional semen analysis and the sperm motility index (SMI) as measured by the sperm quality analyser (SQA), and to evaluate these in relation to the fertilization and/or pregnancy outcome of assisted reproduction. SMI determinations and conventional semen analyses were performed on 223 samples from subfertile men in two laboratories in Leuven (n = 136) and Antwerp (n = 87), and on spermatozoa prepared on a Percoll gradient (n = 136) used for treatment of male factor infertility in 57 cycles of intrauterine insemination (IUI), 44 attempts at in vitro fertilization (IVF) and 31 attempts at intracytoplasmic sperm injection (ICSI). SMI values for native semen correlated significantly with sperm concentration, motility and morphology. Multiple regression analysis revealed sperm concentration after preparation, and the concentration of motile spermatozoa with normal morphology and SMI (before preparation) to be the independent determinants for SMI after preparation. SMI values were significantly higher after, than before, preparation (p < 0.0001). In regular IVF (n = 44) the percentage of fertilized oocytes correlated significantly (p < 0.05) with sperm motility (A + B%, r = 0.33), with the percentage of spermatozoa with normal morphology (r = 0.46) before preparation, with the values of SMI both before and after preparation (r = 0.54, r = 0.48), with sperm concentration (r = 0.34) and with the motile sperm concentration (r = 0.29) after preparation. For the occurrence of pregnancy (all treatment methods), comparison of areas under ROC curves (AURC) indicated motile sperm concentration after preparation, as well as SMI both before and after preparation, to have the highest AURC, with no significant difference between these values as far as predictive power was concerned. These results indicate that the SQA allows for rapid evaluation of sperm characteristics and of the effectiveness of sperm preparation techniques. However, it is not superior to conventional semen analysis in predicting the outcome of assisted reproduction.

Female↗
PubMed1998

Transvaginal hydrolaparoscopy as an outpatient procedure for infertility investigation.

A new technique called transvaginal hydrolaparoscopy is described for the exploration of the tubo-ovarian structures in infertile patients without obvious pelvic pathology. It aims to be an acceptable alternative to diagnostic laparoscopy, a standard but not innocuous procedure which infrequently reveals pathology in the asymptomatic patient. Transvaginal hydrolaparoscopy copy is performed under local anaesthesia using a small diameter optic with the patient in the dorsal position. Cavity distension is achieved with normal saline. Transvaginal hydrolaparoscopy does not provide the familiar and panoramic view of the pelvis given by laparoscopy, but it does have several advantages. These include accurate and atraumatic inspection of adnexal structures without manipulation, with the opportunity to perform dye hydrotubation and salpingoscopy. The risks of a general anaesthetic are avoided, and there is less risk of trauma to major vessels. The high patient acceptability makes transvaginal hydrolaparoscopy suitable as an early stage procedure in the investigation of infertility and as a repeat or second look procedure. Minor operative procedures such as biopsy and adhesiolysis can also be performed. In patients with obvious pelvic pathology, diagnostic laparoscopy will obviously remain the procedure of choice. Transvaginal hydrolaparoscopy deserves full evaluation of its accuracy, risks and benefits before it can be accepted as a new first line technique in gynaecological practice.

Ambulatory Care↗
PubMed1998

Endoscopic visualization of the process of fimbrial ovum retrieval in the human.

The process of ovum retrieval by the fimbriae in the human still remains elusive. Animal studies have suggested that ova can be 'sucked' into the oviduct by negative pressure caused by muscular contractions of the tube, while laparoscopic observations in women have indicated a close relationship between fimbriae and the ovulating ovary. Here, a case is described in which the process of ovum retrieval was observed directly using a new endoscopic technique, called transvaginal hydrolaparoscopy. The access is through the posterior fornix of the vagina and saline is used for distension. The tubo-ovarian structures during the process of ovum retrieval were visualized under fluid. The fimbriae on the ovulatory side appeared congested and tumescent and showed pulsatile movements synchronous with the heartbeat. The cumulus mass was adherent to the fimbriae and released from the site of rupture by the sweeping movements of the fimbriae until it disappeared between the rigid fimbrial folds. To the best of our knowledge this is the first direct observation of the process of ovum retrieval in the human. Vascular congestion causing erection and pulsatile movements of the fimbriae play a role in the retrieval of the ovum. The retrieval process from the site of rupture is slow and transport is achieved by ciliary activity only. The fimbrial changes are apparently controlled by the ovulatory ovary.

Adult↗
PubMed1997

Ovarian and extraovarian sources of immunoreactive inhibin in the chicken: effects of dexamethasone.

The present study investigates whether besides the ovary, extragonadal sources contribute to the total amount of immunoreactive inhibin in the plasma of the domestic hen. A comparison of the inhibin content of different organ shows that, expressed per milligram of tissue, the adrenal ranks second only to the ovarian granulosa layer. To explore the contribution of the adrenals to plasma inhibin, dexamethasone (100 micrograms/kg BW) was injected i.v. into intact, ovariectomized, and sham-operated hens. Control animals of each experimental group were injected with saline (0.9% (w/v) NaCI). Dexamethasone significantly (P < 0.05) decreased plasma inhibin concentrations in the three groups. The suppressive effect of dexamethasone in intact hens, however, was caused by a direct effect of this synthetic glucocorticoid on the gonads. Indeed, dexamethasone decreased the production of inhibin by granulosa cells in vitro and also lowered the immunoreactive inhibin concentration in ovariectomized animals. The decreased plasma inhibin concentration in ovariectomized animals is probably due to a direct effect of dexamethasone on the adrenals. Adrenal cells produced immunoreactive inhibin in vitro. The inhibin secretion by adrenal cells was significantly (P < 0.05) depressed by dexamethasone. In conclusion, the ovary is the major source of plasma immunoreactive inhibin in the laying hen. The presence of substantial amounts of immunoreactive inhibin in the adrenal, the secretion of inhibin by cultured adrenal cells, and the decreased immunoreactive inhibin in ovariectomized animals treated with dexamethasone indicate that the adrenal is a likely source of extragonadal inhibin. The nature and the role of this adrenal inhibin remain to be investigated.

Adrenal Glands↗
PubMed1997

Evidence for the presence of immunoreactive inhibin in extragonadal tissues of ovariectomized ewes.

Six ewes were ovariectomized to determine the immediate and long-term effects of removal of ovaries on the immunoreactive concentrations of FSH, LH and inhibin. Three months after ovariectomy, ewes were slaughtered and tissue samples of brain, pituitary, spleen, liver, perirenal fat, lung, kidney, adrenals and uterus were collected to determine the immunoreactive inhibin content. Both gonadotrophins, FSH and LH, increased significantly after ovariectomy. The increase of FSH, however, was more pronounced and remarkably faster than the changes of LH after ovariectomy. Immunoreactive concentrations of inhibin decreased sharply as early as 15 min after ovariectomy and subsequently decreased more gradually until 2 weeks after surgery. From this moment on, the level stabilized at 56% of the initial value. In control ewes, a considerable amount of immunoreactive inhibin is found in tissue samples of ovary, lung, kidney, pituitary and spleen. After ovariectomy, the level of immunoreactive inhibin decreased in spleen and lung samples while an important increase of immunoreactive inhibin is found in adrenals and pituitary. These results demonstrate a differential regulation of LH and FSH after ovariectomy and support an involvement of inhibin only in the immediate changes of FSH after ovariectomy in sheep. They further suggest that the adrenals and the pituitary may be extragonadal sources of inhibin. To explore the eventual contribution of the adrenals to circulating inhibin, dexamethasone (1.4 mg/ewe) and ACTH (200 IU/ewe) were in a following experiment injected intravenously in control and ovariectomized ewes. The lack of any effect of dexamethasone or ACTH on the plasma concentration of immunoreactive inhibin indicate that adrenal inhibin probably does not contribute to circulating inhibin.

Adrenocorticotropic Hormone↗
PubMed1997

Cumulative pregnancy and live birth rates after gamete intra-Fallopian transfer.

To evaluate the efficacy of gamete intra-Fallopian transfer (GIFT) the Kaplan-Meier life table method was used to analyse a patient cohort treated with GIFT between 1991 and 1994. In a tertiary referral centre for reproductive medicine, 1628 women with a median age of 33 years and various causes of infertility were included to calculate cumulative pregnancy and live birth rates. Age and cause of infertility were main factor variables and the study was based on a total of 2941 consecutive GIFT cycles, leading to a first clinical pregnancy, and 3052 cycles, leading to a first live birth. The cumulative pregnancy and live birth rates were 49.6 and 38.8% respectively, after three initiated cycles and 64.1 and 52.0% respectively, after five initiated cycles. The multiple pregnancy rate was 22.6%. The implantation rate of 13.1% after GIFT demonstrates that the developing embryo benefits from a period of exposure within the environment of the Fallopian tube. The present results indicate that approximately 50% of couples will have at least one live baby after five initiated GIFT cycles. Advancing age was a major negative prognostic factor for the cumulative live birth rate because of higher cancellation rates, lower implantation rates and higher pregnancy failure rates.

Adult↗
PubMed1996

Inhibin and activin have antagonistic paracrine effects on gonadal steroidogenesis during the development of the chicken embryo.

Primary cultures of gonadal cells from chicken embryos were used to explore the paracrine role of inhibin and activin during gonadal development. Fetal testicular and ovarian cells secreted high amounts of immunoactive inhibin. FSH caused a dose-related increase of cAMP and immunoactive inhibin concentrations in testicular cell cultures. Postreceptor signalling through the protein kinase A (PKA) pathway was confirmed by additional experiments with 8-bromo-cAMP, 3-isobutyl-1-methyl-xanthine (MIX), prostaglandins, forskolin, and choleratoxin. The relative ability of these agonists to stimulate cAMP production did not always correlate with their ability to stimulate inhibin secretion. Experiments with phorbol 12-myristate 13-acetate suggested that the regulation of immunoactive inhibin secretion also involves the protein kinase C (PKC) pathway. In addition, it was shown that recombinant human (rh)-inhibin increases the conversion of pregnenolone to androgens whereas rh-activin has the opposite effect. Recombinant human follistatin, an activin-binding protein, antagonized the actions of rh-activin and to a lesser extent those of rh-inhibin. In conclusion, these results show that during the development of the chicken embryo, gonadal inhibin secretion may be regulated by hormones and by local factors such as prostaglandins. Cross talk between the PKA and PKC pathways may be involved in this regulation. Recombinant human inhibin and rh-activin may have antagonistic roles in the paracrine control of gonadal steroidogenesis.

Activins↗
PubMed1996

Dimeric inhibin A and alpha-subunit immunoreactive material in maternal serum during spontaneous and in vitro fertilization pregnancies.

To increase our understanding of the nature and source of immunoreactive inhibin-related material during pregnancy, we studied inhibin secretion in women pregnant after spontaneous conception and after in vitro fertilization (IVF). Two solid phase enzyme-amplified immunoassays (EASIAs) were used to measure the inhibin A dimer and inhibin alpha-subunit immunoreactivities (alpha-inhibin). In spontaneous pregnancies, levels of both inhibin A and alpha-inhibin were low during the first two trimesters of pregnancy, but a significant increase was observed toward the end of gestation. Both assays confirmed that inhibin concentrations in IVF pregnancies exceeded those in spontaneous pregnancies during the entire first trimester. Moreover, the two assays displayed discordant profiles. The alpha alpha-EASIA, which detects all alpha-inhibin immunoactivity, displayed a major peak during the follicular phase and a second broader peak during the luteal phase and corpus luteum rescue. A progressive decline was observed during the subsequent weeks. EASIA measurements for inhibin A revealed distinct peaks during the follicular phase, the luteal phase, and the hCG peak. A marked fall, however, was seen at the time of corpus luteum rescue. In summary, these data indicate that the nature of the immunoreactive material changes considerably during the different phases of pregnancy. The available evidence further points to an ovarian source of dimeric inhibin in early pregnancy and a placental source toward the end of pregnancy.

Adolescent↗
PubMed1996

Incongruent follicular development reduces gamete intrafallopian transfer pregnancy rate.

OBJECTIVE: To test the null hypothesis that asymmetric or incongruent follicular development does not influence GIFT pregnancy rates (PRs). DESIGN: A prospective comparative study. SETTING: Tertiary referral center for infertility. PATIENT(S): Ninety-three consecutive infertile patients having GIFT. INTERVENTION(S): Controlled ovarian hyperstimulation and GIFT. MAIN OUTCOME MEASURE(S): The incongruity ratio as a parameter of the asymmetry in follicular development and the clinical PR. RESULT(S): An inverse relationship was observed between the degree of incongruity and the clinical PRs. In patients with an incongruity ratio < 1.5, the clinical PR was 56.1%. In patients with an incongruity ratio > or = 1.5, the clinical PR was only 17.3%. CONCLUSION(S): Incongruent follicular development during controlled ovarian hyperstimulation has a marked negative influence on the outcome of GIFT cycles. Factors such as side of the gamete transfer and oocyte quality did not account for the observed differences.

Adult↗